Electric heater



July 16, 1940. c. J. SOMERS ELECTRIC HEATER Filed Nov. 6, 1939 a i a a W .Z m m a w w w a 9/ 0 4y v %v5/ &3 Pro B 4 7/3 7 I IN a:

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TF1 d j. .6 w V Patented July 16, 1940 UNITED. STATES PATENT OFFICE 2,208,087 ELECTRIC HEATER Carlton .I. Semen, Osage, Wyo. Application November 6, 1939, Serial No. 303,148

1 Claim. This invention relates to electric heaters and has for an object to provide a simplified device of this character adapted to economically create circulation in an oil well to accelerate production.

A further object is to provide a device of this character which will be so constructed that the heat element will be protected from contact with sand and thus short circuits will be eliminated.

A further object is to provide a device of this character which may be used as a permanent heater in a pumping well without interfering with the pumping operation.

A further object is to provide a device of this character which will be formed of a few strong simple anddurableparts, which will be inexpensive to manufacture, and which will not easily get out of order.

With the above and other objects in'view the invention consists of certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modifications may be resorted to within the scope of the appended claim without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawing forming a part of this specification:

Figure l is a longitudinal sectional view of an electric heater constructed in accordance with the invention and disposed in an applied position at the bottom of an oil well.

Figure 2 is a cross sectional view taken on the line 2-2 of Figure 1.

Figure 3 is'a cross sectional view taken on the line 33 of Figure 1.

Referring now to the drawing in which like characters of reference designate similar parts in the various views, Ill designates a metal tube which may be connected to the bottom of a metal tube l I to be let down into the oil well below the well casing II. An insulating block I3 is secured to the tube H and engages the casing to center the tube ill in the casing.

A metal cylinder l4 surrounds the lower end of the tube It and is provided with a funnel-shaped bottom l5 in.which is disposed a block l6 of insulating metal. The lower end of the tube I0 is provided witha flange ll which is bolted as shown at l8 to the insulating block I 6 which latter is secured by a bolt l9 to a metal diaphragm which extends across the funnel-shaped bottom of the casing. A tube 2| is screwed into the funnel-shaped bottom to elevate the cylinder to the lowest point to be heated.

The cylinder I4 is closed at the top by a conical ly around the rods 24 in the form of a helix.

block 22 of insulating material which may be screw threadedly engaged as shown at 23 with the tube. A plurality of rods 24 ofinsulating material are threadedly engaged at the upper ends in the bottom of the insulating block 22 and are connected at their lower ends by an insulating flange 25 spaced above the bottom flange ll of the tube H). A resistance wire 26 is connected at one end to the tube l0 and is coiled longitudinal- The 10 upper end of the resistance wire is connected to a conductor 21 which extends through a guide opening 23 in the insulating block 12 and is connected at the upper end to a grounding device 29 which will now be described. 1 The grounding device comprises a disk 30 which is supported on an insulating collar 3| formed on the tube. A plurality of metal contact arms 33 having rounded contact edges 34 are mounted in slots 35 formed in the disk 30 and are plvotally U secured to the disk by a ring 36 engaged in the groove 32 in the disk and in openings 31 in the contact arms 33; Helical springs 38 are connected to the contact arms below the disk, as best shown in Figure 2, and hold the upper ends of the $5 arms rocked outwardly to engage the casing l2 and maintain good electrical contact with the casing. The conductor 21 is insulated wire of stranded type and the strands 39 are separated and connected to respective contact arms 33.

The tube i0 is provided with a plurality of perforations 40 below the contact arms 33 and also the tube is provided with a plurality of perforations 4| just above the bottom flange H. The cylinder [4 is provided near the top with perfo- 35 rations 42.

In operation the tube II is connected to one terminal of a source of electricity so that the current for actuating the heater will pass from the tube l0 through the heating coil 24, con- 40 ductor 21 and contact arms 33 to the well casing l2 of the oil well. The coil when heated will cause a circulation of oil, as indicated by the arrowheads in Figure 1, the oil entering the tube l0 through the upper perforations 40, leaving the tube In through the lower perforations M, then rising through the cylinder H of the heater and emerging therefrom through the perforations 42.

From the above description it is thought that the construction and operation of the invention will be fully understood without further explanation.

What is claimed is:

An electric heater for oil wells including a length of tube adapted to be inserted within the 2 menace? casing of an oil well and lowered to a point below the casing, an electric heating element surrounding the tube and insulated therefrom, a cylinder housing the heating element secured to the lower end of the tube and insulated therefrom, there being oil inlet perforations in the tube above the cylinder and oil outlet perforations in the cylinder near the upper end thereof, a conductor extending from the heating element to the exterior of the cylinder, an insulated disk surrounding the tube in the well casing, metal contact arms pivotally connected to the disk and connected to said conductor, and springs connecting the contact arms at the lower ends thereof together to hold the upper ends of the contact arms in good electrical contact with thecasing.

CARLTON J. SOMERS. 

